Equipment of this type is known in the prior art from EP-A1-0 655 264 which shows a training device provided with foot plates which are displaceable along a beam against the tractive force of a cable connected to the foot plates, the cable in turn being influenced by a motor which is controlled by means of a control unit. The control unit makes it possible to predetermine the characteristics of the load exerted by the motor.
The equipment according to the invention is similarly provided with a device which is controllable in order to determine the characteristics of the load which acts on an operating means, e.g. footplates, handles or levers of various types, attached to the device. In particular, the load on the operating means is adjustable in such a way that the muscle group in question is made to work eccentrically.
A muscle has namely essentially three different ways of working. It can contract, and thereby for example bend ajoint, or it can work statically, i.e. be tensed without either becoming shorter or longer. Finally, the muscle can also work eccentrically; i.e. attempt to contract at the same time as it is forced to become longer.
A now scientifically grounded fact is that the power which muscles develop is greatest when they work eccentrically, next greatest when they work statically and least when they work concentrically. Top sportsmen have with this fact as a foundation pursued eccentric fitness training since the middle of the 80's, because it has been accepted that if every muscle is strongest when it works eccentrically then the most effective way of training them should also be through eccentric training. In 1991, Per Egil Rettsnes at Norges Toppidrottscentrum in Oslo, started a not yet published scientific comparison of the different methods of fitness training. In 1995, published scientific comparison of the different methods of fitness training. In 1995, the studies showed that eccentric fitness training is more effective than conventional concentric fitness training.
Concentric fitness training is consequently defined as training with the same load in both the concentric and the eccentric phases of a fitness training action.
Excentric fitness training is defined as training where the load increases at the transition from the concentric to the eccentric phase of a fitness training action.
Training equipment according to the prior art for eccentric training has in the rule a motor which produces the necessary load on the operating means. The motor can be a rotating motor or a linear motor which, for example, is driven electrically, hydraulically or pneumatically and which is controlled by a control unit which is programmable to increase the load at the transition from the concentric to the eccentric phase.
Sometimes, for example, direct current motors or hydraulic cylinders are used and for the control of these, the necessary special control units with associated electronic equipment are relatively complicated and costly and, moreover, the electronics are often unreliable and sensitive to disturbances and external influences. Furthermore, this "virtual" equipment lacks real weights, which is a disadvantage as the size and shape of the weights are experienced by many as a psychological indicator of the size of the load. In general, even the rattle of the weights at the end positions is experienced as an acknowledgement of the work performed.